1. Field of the Invention
The present invention relates to a lambda type direct suspending overhead contact system for electric railway which is less costly than conventional systems.
2. Description of the Prior Art
Tests of aluminum wire having steel tape core have begun with the idea of using them instead of the conventional copper contact wire. Aluminum wire having steel tape core as a contact wire is made by encapsulation of a steel tape in aluminum and is referred to as steel-aluminum contact wire. The steel-aluminum contact wire can be suspended under high tension whereby it is possible to suspend it by lambda type suspension wires without using a messenger wire.
The lambda type suspension wire has anchor ears at both ends to hold a contact wire for a railway. The center of the suspension wire is held in lambda form by an insulator fitting connected to a fixed beam. It is, however, indispensable to bend the different catenaries formed at both sides of the anchor ear. The bent part of the catenaries of the contact wire, however, causes problems for high speed running of a car.